iCircuit 4+

I’m an electronics technician, with 41 years of experience in the industry. This app is nothing short of fantastic! This is perfect for students, techs, and engineers at all levels. The basic program is fine for most techs and hobbyists. Engineers and more advanced people would be interested in the pro version.

The latest version, 1.12, includes many requested updates to the interface, and more components. This is a very large update to this application. Thanks to the developer.

As other reviewers have noted, I have tried other simulators, but I keep coming back to iCircuit.

Got fooled by the nice UI and thought I could use it instead of free ltspice (or other similar open tool).
Apparently this tool doesn't go beyond sleek UI even in the most basic and trivial capabilities.
You have to use equivalent schematic for every single passive because it doesn't have a concept of even such trivial things as parasitic resistance/capacitance/inductance (which seems so trivial to implement - I wouldn't think it is not available here). Let alone - parametrized models for semiconductors, not even reverse breakdown for diodes. Now modelling passives is annoying but reasonably feasible, modelling semiconductors is something is something you wouldn't even consider doing, especially when they have proper spice models and can be simply plugged in into any proper software.

Giving it 2 stars instead of one just because it is a nice visual tool for school students to explain basics of how elements work and give ability to create some "ideal world" schematics in a nice UI.

I have bought this app for ipad and mac. The basic functionality is there, and I really like the visualization of current flow when a circuit is completed, but all of the UI interactions feel really hard to use, a few examples:

The marquee (selection) mechanism should have the option of a bounding box, the "draw a selection" behavior goes against decades of muscle memory (not to mention the polygon "winds", making a selection action that much worse).

The fields for modifying a component's properties don't appear to be linked in a focus ring, and therefore I can't tab between them.

Selecting a bunch of components and then dragging causes wiring to get messed up. Most of the time, I'm just trying to clean things up, but this results in the digram junctions changing.

The forward-delete (on a fullsized keyboard) doesn't work to delete, only the delete key.

On ipad, the toggling between draw and delete modes is extremely frustrating, for example, adding a component, but then, tapping on it causes it to be deleted if you've left the delete mode enabled.

These apps aren't cheap, and I bought the Mac version because I hoped the keyboard/mouse interactions would make things easier, but honestly, the UI is almost more frustrating than on iPad.